code: def forward(self, x):
      return F.normalize(self.proj(x), p=2, dim=1)
  
imports: import paddle
  import paddle.nn
  import paddle.nn.functional
  from paddleseg.cvlibs import manager, param_init
  from paddleseg.models import layers
label_desc: Use image node_id 2 for calling the ProjectionHead obj's underlying member method code with example usage: obj.forward(x) and returns: F